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Full text of "The manufacture and properties of iron and steel"

24                                              INTBODUOTION".
I find that it takes more carbon to give a certain, tensile strength in basic than in acid steel, even when the phosphorus is the same, and this is a bad thing because every increase in carbon gives a better chance for segregation and lack of uniformity. I do not say that this in itself proves basic steel to be unreliable, but it does indicate that acid steel may be preferable in some cases.
SPECIFICATIONS ON STETICTUEAL MAT'EBIAL.
It is the custom for engineers to specify the kind of steel they wish, and what the physical requirements shall be. It sometimes happens that the engineer does not understand all about the different kinds of steel and does not know what elongation and reduction of area should be obtained in each case. He often takes the first specification he finds and adds to it some special idea which has been impressed upon his mind. There are many such specifications used by engineers. Some of them are out of date, but hold their place because the longer they have been in use the more reverence they receive from certain, people, and the more proud of his work is the author. His name attached to a set of specifications is a constant advertisement, and arouses a pardonable feeling of self-satisfaction. These conditions, however, do1 not serve scientific progress.
In 1895 the' Association of American Steel Manufacturers adopted a set of specifications, and although it was claimed that it was not the place of the manufacturers to do this, yet the users of structural material eagerly grasped these specifications as filling a long-felt want, and they are the basis of business to-day. There are two> facts which may well be kept in mind :
First: The steel manufacturers in session assembled may be supposed to know something about steel.
Second: It is not for their interest to advocate a bad material. It might be for the interest of one of them to pass a bad lot of steel on a single contract, but as a whole they have no incentive to plead the cause of something they think is bad.
The steel makers are not a unit in all matters, but they agree in some things. Most of them believe that Bessemer steel will do for buildings, highway bridges and similar purposes. They believe that open-hearth steel should be used for railway bridges, for boilers, for locomotive forgings and other purposes where the steel